1. Field of the Invention
The present invention relates to an encoding processing and a decoding processing of image data.
2. Description of the Related Art
Data capacity is limited in the data processing using a storage medium such as a memory card. As the prior arts of such data processing, “Image Communications Apparatus” of Unexamined Japanese Patent Publication No. HEI 01-226272 and “Copying Device” of Unexamined Japanese Patent Publication No. SHO 63-110870 have been introduced. In these arts, while data having a feature that the data is to be used only once is being used, a part of area used for storing the data is released. Then, the released part is used for another use, which enhances the processing efficiency.
Problems to be Solved by the Invention
Recently, the storage medium, such as a memory card, has become to have a high capacity. Therefore, such storage medium is often used as an image data storage medium of, for instance, a cellular equipment. However, since the storage capacity in current use is about the extent of 128 MB, it is impossible to maintain image data of high quality for a long time, even if the data is compressed by utilizing an encoding technology. Therefore, it is desired to perform an effective data processing in the limited data capacity. Concretely, reducing a load of decoding process of image data, and making encoded image data used for the decoding processing have a high quality and a high compression rate is desired.
In the conventional art stated above, when data which can be used only once is being processed, an area having been already used out of a data storage area is released to be effectively utilized. The object of utilizing the data area which has been released in the data processing system of the conventional art is to advance a start timing of another data processing. Therefore, the object of the conventional art does not deal with the stated problems to be solved relating to the decoding process of image data.
It is one of objects of the present invention to solve the above stated problems. Namely, when a decoding process is performed for image data in a limited data capacity by using a storage medium such as a memory card, it is one of the present invention to reduce a load of decoding process of image data, and to make encoded image data used for the decoding processing have a high quality and a high compression rate.